英文關鍵字
agriculture
balkan
banks
big
blue
channel
cloud
color
country
deep
delta
down
eastern
ecology
environment
europe
european
flow
fresh
geography
grass
green
grow
industry
irrigation
landscape
large
mediterranean
mountain
nature
pan
plain
plant
river
rural
shores
sky
southern
stream
territory
travel
valley
view
water
watercourse
wide